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Physicists Argue That Black Holes From the Big Bang Could Be the Dark Matter
It was an old idea of Stephen Hawking’s: Unseen “primordial” black holes might be the hidden dark matter. A new series of studies has shown how the theory can work.
A New Cosmic Tension: The Universe Might Be Too Thin
Cosmologists have concluded that the universe doesn’t appear to clump as much as it should. Could both of cosmology’s big puzzles share a single fix?
An Alternative to Dark Matter Passes Critical Test
Modified gravity theories have never been able to describe the universe’s first light. A new formulation does.
The Hidden Magnetic Universe Begins to Come Into View
Astronomers are discovering that magnetic fields permeate much of the cosmos. If these fields date back to the Big Bang, they could solve a major cosmological mystery.
A Surprise Discovery Points to the Source of Fast Radio Bursts
After a burst lit up their telescope “like a Christmas tree,” astronomers were able to finally track down the source of these cosmic oddities.
What Might Be Speeding Up the Universe’s Expansion?
Physicists have proposed extra cosmic ingredients that could explain the faster-than-expected expansion of space.